Source of one of the safest of all insecticides. White daisy flowers contain pyrethrins which act directly on the nervous systems of aphids, mites, leafhoppers, cabbageworms and other insects. Will not harm fish, waterfowl, plants or mammals. To make pyrethrum spray, mix 15mL/1Tbsp freshly ground dried flowers with 2L/2qt hot water. Add a little soap and let stand.